We plan to continue to expand the work on biogenesis of the transformed state on the receptors for carcinogenic hydrocarbons. We will attempt to prepare affinity columns using aflatoxin B1 bound to an immobile matrix in order to begin isolation and purification of receptor material. This will also be done for, at least, one other hydrocarbon. We will continue to examine the kinetics of receptor-ligand binding using aflatoxin B1. The data received will be examined with respect to normal and transformed cells. We plan to initiate studies of the genetics of cells as they progress through to the transformed state. We plan to treat early passage cells with environmental mutagens and carcinogens and determine the frequency with which variant cells are formed with respect to resistance to the tested compounds, 6-thioguanine, chromosome number, plating and cloning efficiencies, population doublings and tumorigenicity. We are eliminating, for the time being at least, our studies with methotrexate as this is being studied with greater competencies in the laboratories of Dr. Shimke at Stanford, and Dr. Hamlin in Charlottesville, Va. We also plan to continue the work of elucidating the totipotency of our cells with respect to the type of tumor formed on animal injection. We plan to continue the maintenance of the transformed state by production of reconstituted cells. That is, isolated cytoplasts and karyoplasts will be fused from both normal and transformed cells. Soft agar response will be evaluated as preliminary monitors of transformation. Karyological data will also be evaluated. Back injection will confirm the preliminary data. We will also continue to evaluate the cybrid studies. All "parents" are to be tested for soft agar growth, karyological data and tumor formation.